Hi all,

I want to build a simple wireless audio relay for my guitar, so I don't
have to use cables to hook it up to the amp/computer. Buying a decent one
would cost around $200 and there's no way in hell I'm spending $200 for a
simple short range radio. I figured I'd make my own.

I'm thinking:

GUITAR -> op amp -> ADC -> radio module

radio module -> DAC -> op amp -> output

Specifications:

- Sample rate: I think 96kHz should be good. CD quality is 44.1 kHz, but I
really want to capture much more than that.
- Resolution: 16 bit sounds about right. I can't find any ADCs with 24 bits
at 96kHz anyway (only a quick search)
- I have some good op amps in mind. Maybe LTC6202
http://www.linear.com/product/LT6202 - low noise, good slew rate, more than
enough GBW, low power, good package, cheap

Radio module:

This is the most complicated part for me. I plan to use a parallel CMOS ADC
to keep it simple (unless someone recommends otherwise) and feed it
directly into the radio module if I can. But if I can't, I don't mind using
a CPLD to interface the ADC to the radio module.

96kHz * 24 bit =3D 2.3Mbit/s
96kHz * 16 bit =3D 1.5Mbit/s

I have no idea which radio chip/module/transceiver to use. Various products
off the top of my head:

- XBee (not enough throughput)
- TI CC1101 type (not enough throughput)
- RFM12 type (not enough throughput)
- Various other ISM transceivers (probably not enough throughput)

- 802.11 wifi modules - these are fast enough, but pretty expensive and
will probably require more than just a CPLD to interface
- CC8531 type http://www.ti.com/product/cc8531 - looks like it was designed
for my purpose. Doesn't look too easy to interface though. This is the best
solution I could find.

Any other ideas?

The whole thing should be as low latency as possible - undetectable by me
(I can notice latencies of more than a few milliseconds, more sensitive
than the average human, and it's very annoying).
--=20
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